Appending to a text field using UPDATE

I would like to update a field that already has data in it and I dont' want to overwrite the existing text. Here is my existing statement

UPDATE wr SET cf_notes = " + tmp_array(24) + " WHERE wr_id = " + data_temp(0)

I would like to add cf_notes + tmp_array(24) to cf_notes. Is this possible in SQL? If so, what is the correct syntax. I have tried 6 different statements and I get a compile error on every statement.

Thanks,

SBRcreate procedure spU_update_table_with_text (
@.key_field_value int,
@.text text = null)
as
declare @.txtptr binary(16), @.insert_offset int
select @.txtptr = textptr(text_field),
@.insert_offset = datalength(text_field) + 1 --or 2 if a space is needed
from your_table
where key_field = @.key_field_value
updatetext your_table.text_field @.insert_offset 0 @.text
return